An experimental study on electro-discharge machining and polishing of highstrength copper-beryllium alloys

An experimental study on the effect of electro-discharge machining (EDM) pa rameters on material removal rate (MRR) and surface quality, when machining high strength copper-beryllium alloys is presented. Processing parameters for rough, finishing and micro-finishing or polishing regimes were analysed , as well as the effect of the introduction of planetary motion and a relax ed oscillation waveform delivered by a relaxation circuit (RC) during finis hing and micro-finishing cuts were studied. The surface integrity of electr o-discharge machined (EDMed) is quantified by measuring the roughness value s, crater diameter and white layer thickness (WLT). Quantification of the e xtended surface damage and its relation to the discharge power, as measured through the product of current intensity (I) and discharge time (t(d)), co ntrollable in a isopulse type generator, is carried out. "Thermal erosion m odels", as justification for the optimal setting of different EDM parameter s and achievement of distinct surface integrity using materials with differ ent thermal properties, are discussed. (C) 2000 Elsevier Science S.A. All r ights reserved.